Lamp extractor and injector



E. M. WAGSTAFF LAMP EXTRACTOR AND INJECTOR Feb. 9, 1960 Filed Sept. 28, 1956 A T TORNE Y IN VEN TOR. Eda/12a M. Wdjataff LAMP EXTRACTOR AND INJECTOR Edwin M. Wagstalf, Galion, Ohio Application September 28, 1956, Serial No.'612,664 Claims. Cl. 294-20 This invention relates to improvements in lamp extractors and injectors.

More particularly my invention relates to the type of lamp extractors and injectors which are used to replace small bayonet type lamps in recessed sockets. Present extractors are of a complicated structure rendering their manufacture relatively costly and are limited in use to mountings wherein there is a substantial clearance between the lamp and the sides of the recess.

It is an object of this invention to provide a frictional gripping tool for removing bayonet mounted objects such as lamps and radio tubes from recessed mountings.

It is a further object of this invention to provide an extractor and injector having a minimum number of work- 'ing parts and which is of' a rugged construction.

It is a still further object of this invention to provide an extractor and injector using simple component parts which are subject to a minimum amount of wear and which have little possibility of malfunctioning.

Yet another object of this invention is to provide an extractor and injector which will be simple and easy to use and which will be economical to manufacture.

A still further object of this invention is to provide an extractor and injector which provides little or no possibility of causing a short circuit.

Another object of this invention is to provide an extractor and injector which may be used in recessed mountings providing only a minimum clearance between the lamp or tube and the sides of the recess.

' These and other objects and advantages of this invention will be apparent from the following description and claims.

In the accompanying drawings which illustrate by way of example various embodiments of this invention:

Fig. l is a top view of my lamp extractor and injector showing the injector mechanism in a withdrawn position;

Fig. 2 is a side elevation view of my lamp extractor and injector also showing the injector mechanism in a withdrawn position;

Fig. 3 is a sectional view along line 3-3 of Fig. 2 and shows the injector mechanism in a withdrawn position in full lines and injecting position in dotted lines;

Fig. 4 is a sectional view along line 44 of Fig. 3.

My lamp extractor and injector as shown in the accompanying drawings comprises a body member 10, a resilient gripping tube 20 and an injecting mechanism 30.

The body of my extractor is preferably of a generally cylindrical form comprising a handle portion 11 and a smaller outside diameter portion 12 which serves as a mounting portion for the resilient gripping tube 20. Extending axially through the body 10 is a bore or hollow portion 13 which is of a uniform diameter throughout except for enlarged diameter portions 14 and 15 which are provided to accommodate mounting collars 36 and 38 to'be later described. The reduced diameter portion 12 of the body is formed as an integral part of the body 10. The outside diameter and length of this reduced United States Patent 0 2,924,481 Patented Feb. 9, 1960 "ice diameter portion 12 will be governed by the size of the lamps which a particular unit is designed to operate upon and by the depth of the recesses in which these lamps are mounted. The outside diameter of the portion 12 should be the same as or slightly larger than the outside diameter of the lamps which are to be extracted. This portion must also be of sufficient length to insure that 'the resilient member 20 will adhere to the portion 12 with sufficient force to allow lamp extraction without disengagement of the tube from the body.

The resilient tube 20 has an inside diameter slightly smaller than the outside diameter of the lamps to be extracted. The length of this tube must be sufiicient to engage the reduced diameter portion 12 of the body and extend therefrom a sufficient distance so that when this sleeve 20 is forced over a lamp the frictional gripping force between the tube and the lamp will be sufficient to remove the lamp without disengagement of the sleeve from the lamp.

The frictional effect is enhanced by axial pull on the tube 20 which tends to elongate due to its resilience and therefore tends to decrease its diameter. Since the tube cannot descrease in diameter in those regions where it grips a bulb, it instead tightens its grip on the bulb. Thus, to a point, depending on the design of structure, resistance to pull produces a tighter grip on the bulb so that the tube 20 will not be inadvertently pulled off a bulb which resists extraction.

While any suitable resilient material may be used in making the gripping tube, a vinyl plastic type material is to be preferred. The use of this preferred type of material is particularly necessary when the extractor is to be used on recess mounted lamps which provide only a narrow circumferential clearance between the lamp and the sides of the recess. By using a vinyl plastic type material which has a high modulous of elasticity a relatively thin walled tube will give the necessary frictional adhesion to the lamp to be extracted thus enabling this device to operate where only narrow clearances are provided.

The injecting mechanism 30 comprises a rod 31 which may be solid or tubular and two pressure tips 32 and 33. The rod 31 is of a diameter to give a loose fit in the bore 13 and is of a length substantially equal to the overall length of the body 10 plus the extension of the resilient tube 20. A lamp pressure tip 32 is mounted upon the lamp engaging end of the rod 31 by soldering, welding, pinning, shrink fitting or any other suitable means. As shown in the drawings, a collar 36 is pro vided which fits around the end of the rod 31. The face 37 of the pressure tip 32 is preferably of an outwardly concave shape to facilitate even pressure distribution over the lamp end and is of a diameter substantially less than the inside diameter of the resilient tube 20 to permit the pressure tip 32 to be easily slidable within the resilient tube 20. A thumb pressure tip 33 is provided at the other end of the rod 31 and, as shown, comprises a mounting collar 38 and aflat pressure plate 39 for com- -fortable application of force by the operator. The tip over the lamp. As noted above, the gripping tube will engage the lamp with sufficient force to permit the lamp to bewithdrawn. merely-by pulling on the handle 11. After extracting thelamp from its socket, the lamp is ejected from the mechanism by holding the body member and pushing the injecting mechanism 31 forward whereby the tip 32. will push on the end: of the lamp and. eject it from the gripping tube. v A I In injectinga lamp into. a recessed socket,thev operator first forces the lamp intov the gripping tube and permits the lamp to push the injecting mechanism into the retractedv position. The lamp may then be forced into its socket by manipulation of the handle 11. After the lamp has been forced into its socket, the extractor is removed by applying force tothe tip 33 of the. injecting mecha nism which serves to hold the lamp in injected position while the operator slides the gripping tube off/of. the lamp by pulling on handle 11. V

i It is to be noted that in. the above structure the only electrically conductive material is in the injector mechanism and that this mechanismcontacts only the end face of the lamp thus minimizing the danger of causing a short circuit. In this regard, I anticipate the making of part or all of the injector'mechanism of. a suitable nonconductive material.

Whilethe operation of this mechanism has been described in conjunction with lamps, it is to be understood that its' use is equally advantageous in any type of recessed mounting of. lamps, light bulbs, radio tubes or the like, and it will be understood that it is capable of further modification, and this. application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as' come within known or customary practice in the art to which the invention pertains, and as may be applied to the essential features hereinbefore set forth and as fall within the scope of the invention or the limits of the appended claims.

Having thus described my in ention what I claim is:

l. A mechanism for extracting from and injecting into side diameter" in e that regionline which tube is: adapted to be stretched radially outwardly by insertion of a bulb and tends toincrease by axial elongation and radial contraction its gripping efiect upon resistance by the bulb to a longitudinal pull and means in the mechanism for ejecting the bulb out of the tube.

2. A mechanism for extracting from and injecting into their sockets miniature light bulbs, or the like, comprising a rigid support body" adapted to be manipulated by the user, a gripping tube of thin resilient elastic insulating material capable of frictionally engaging the material of the light bulb and having an-innerdiameter less than the diameter of a light bulb of the size: adapted to be injected or extracted by the mechanism which tube engages the outersurf'ace of a--portion-of the body and constitutes the full outside diameter in that region and extends beyond the body and which tube is adapted to be stretched radially outwardly by insertion of a bulb and tends to increase. by axialfelongation andradialcontraction the gripping effect upon resistanceby the bulb to longitudinal pull, .and an injector ma, extending through the body so thatone, end lies withinthe. gripping't'ube, said rod being slidably mountedwithi'n and longer than the body. 7

3. The mechanism of claim 2 in which the body. is rigid and elongated and theinjector rod is provided at each end with pressure distributing tips.

4. The mechanism. oi claim: 3- in which the body is generally cylindrical inv form and the, injector. rod is axially slidable within the body and the grippingtubeis a hollow cylinder of uniform. wall. thickness.

5. The mechanism ofi claim. 4. in which the cylindrical body has its diameter decreased. at; one end to accommodate the gripping tube which isv held in place thereon after being stretchedover the reduced diameter, portion of the body.

References Cited in the fil'e of, this patent UNITED STATES. PATENTS 977,158 Berkstresser Nov. 29', 1910 1,686,250 Page Oct. 2'; 1928 2,534,799 Schwinn Dec. 19, 1950 2,607,620 Oliveri Aug. 19', 1952 2,651,229 Lenz Sept. 8, 1953 FOREIGN PATENTS 140,934 Australia Apr; 23, 1951 

